Structures and Methods for Forcing Coupling of Flow Fields of Adjacent Bladed Elements of Turbomachines, and Turbomachines Incorporating the Same

• US 20170097010A1
• Filed: 12/15/2016
• Published: 04/06/2017
• Est. Priority Date: 01/23/2013
• Status: Active Grant

• Current Assignee: Concepts NREC, LLC
• Original Assignee: Concepts NREC, LLC
• Inventors: Japikse, David
• Granted Patent: US 10,590,951 B2
• Time in Patent Office: Days
• CPC Class Codes: B23P 15/006 turbine wheels
• CPC Class Codes: F01D 25/06 for preventing blade vibration means on blade-carrying members or blades F01D5/00
• CPC Class Codes: F01D 5/142 of the blades of successive rotor or stator blade-rows
• CPC Class Codes: F01D 5/145 Means for influencing boundary layers or secondary circulations for compressors F04D29/68
• CPC Class Codes: F01D 5/225 by shrouding
• CPC Class Codes: F01D 9/041 using blades F01D5/148 takes precedence
• CPC Class Codes: F01D 9/045 for radial flow machines or engines
• CPC Class Codes: F04D 1/00 Radial-flow pumps, e.g. centrifugal pumps; Helico-centrifugal pumps adapted for pumping specific fluids F04D7/00; priming or boosting F04D9/00
• CPC Class Codes: F04D 17/10 for compressing or evacuating
• CPC Class Codes: F04D 29/162 of a centrifugal flow wheel
• CPC Class Codes: F04D 29/167 of a centrifugal flow wheel
• CPC Class Codes: F04D 29/245 for special effects
• CPC Class Codes: F04D 29/281 for fans or blowers
• CPC Class Codes: F04D 29/284 for compressors
• CPC Class Codes: F04D 29/324 Blades
• CPC Class Codes: F04D 29/325 for axial flow fans blade mountings F04D29/34, blades F04D29/38
• CPC Class Codes: F04D 29/384 characterised by form
• CPC Class Codes: F04D 29/444 Bladed diffusers
• CPC Class Codes: F04D 29/448 bladed diffusers
• CPC Class Codes: F04D 29/542 Bladed diffusers fixing blades to stators F01D9/042
• CPC Class Codes: F04D 29/544 : Blade shapes
• CPC Class Codes: F04D 29/666 : by means of rotor construction or layout, e.g. unequal distribution of blades or vanes
• CPC Class Codes: F04D 29/685 : Inducing localised fluid recirculation in the stator-rotor interface
• CPC Class Codes: F05D 2240/121 : related to the leading edge of a stator vane
• CPC Class Codes: F05D 2240/126 : Baffles or ribs
• CPC Class Codes: F05D 2240/303 : related to the leading edge of a rotor blade
• CPC Class Codes: F05D 2250/52 : Outlet
• CPC Class Codes: Y10T 29/49229 : Prime mover or fluid pump making

Abstract

Turbomachines having close-coupling flow guides (CCFGs) that are designed and configured to closely-couple flow fields of adjacent bladed elements. In some embodiments, the CCFGs may be located in regions extending between the adjacent bladed elements, described herein as coupling avoidance zones, where conventional turbomachine design would suggest no structure should be added. In yet other embodiments, CCFGs are located upstream and/or downstream of rows of blades coupled to the bladed elements, including overlapping one of more of the rows of blades, to improve flow coupling and machine performance. Methods of designing turbomachines to incorporate CCFGs are also provided.

Claims

1. A turbomachine, comprising:

a first bladed element having a first blade region containing a plurality of first blades; and

a second bladed element having a second blade region containing at least one second blade, wherein the second blade region is located adjacent to and downstream from the first blade region;

wherein the first bladed element has a rotational axis and at least one of the plurality of first blades has a trailing edge located at a radius, r₂, from the rotational axis, the turbomachine further including a close coupling flow guide (CCFG) having a leading edge located at a radius, r_c, from the rotational axis, and wherein r_c/r₂ is less than about 1.

2. A turbomachine according to claim 1, further comprising a coupling avoidance zone extending between the first blade region and the second blade region, and wherein the CCFG is located in the coupling avoidance zone.

3. A turbomachine according to claim 1, wherein the second bladed element comprises a plurality of second blades arranged and configured into a low solidity blade row.

4. A turbomachine according to claim 3, wherein the second bladed element further comprises a plurality of third blades arranged and configured into a tandem blade row positioned downstream of the low solidity blade row, the tandem blade row having a lower blade count than the low solidity blade row.

5. A turbomachine according to claim 3, wherein the low solidity blade row comprises a plurality of flat plates.

6. A turbomachine according to claim 1, wherein the CCFG comprises a contoured surface.

7. A turbomachine according to claim 6, wherein the contoured surface has a leg overlapping the first blade region.

8. A turbomachine according to claim 7, wherein a portion of the contoured surface is located in the second blade region.

9. A turbomachine according to claim 1, wherein the CCFG comprises a rib.

10. A turbomachine according to claim 9, wherein a first portion of the rib is located in the first blade region and a second portion of the rib is located in the second blade region.

11. A turbomachine according to claim 9, wherein the CCFG further comprises a second rib and a trough, the trough located between the rib and the second rib.

12. A turbomachine, comprising:

a first blade row including a plurality of blades having trailing edges; and

a close-coupling flow guide (CCFG) located proximate the first blade row, wherein the CCFG overlaps the trailing edges and is configured to guide a portion of working fluid in the turbomachine.

13. A turbomachine according to claim 12, further comprising a hub surface and shroud surface, wherein the CCFG is formed in at least one of the hub surface and the shroud surface.

14. A turbomachine according to claim 13, wherein the CCFG includes at least one channel formed in the shroud surface.

15. A turbomachine according to claim 14, further comprising a diffuser located downstream of the first blade row, the diffuser having an inlet and an exit, wherein the at least one channel extends downstream of the diffuser inlet.

16. A turbomachine according to claim 15, wherein the at least one channel extends at least to the diffuser exit.

17. A turbomachine, comprising:

a hub and shroud forming a diffuser passageway therebetween, the diffuser passageway having an inlet; and

an impeller rotatably disposed adjacent the diffuser, the impeller having a plurality of impeller blades with trailing edges, wherein the trailing edges are located downstream of the diffuser passageway inlet.

18. A turbomachine according to claim 17, further comprising a plurality of diffuser blades having leading edges, wherein a portion of the leading edges are located upstream of the impeller blade trailing edges.

19. A turbomachine according to claim 18, wherein the diffuser blades have a pressure side and a suction side, wherein the leading edges have an asymmetry about a diffuser blade centerline extending from the hub to the shroud, the asymmetry formed by a chamfer on either the pressure side or the suction side of the diffuser blades.

20. A turbomachine according to claim 17, further comprising at least one channel located in the shroud that extends in a flowwise direction and overlaps the trailing edges.